Conventionally fastening systems for suspended ceiling grid systems involve the use of punches or pop rivets or other labor costly techniques. Such system are not readily forgiving of error nor do they permit ready control or horizontal adjustment of connecting tees or moldings at right angles to tees. Moreover, if horizontal movement is not controlled during construction, slippage and failure may occur.
The use of punching and pop riveting in addition to being labor intensive, also results in a marked or unclean exposed surface connection.
Conventionally the starting main tees may be wired tight to the wall through the use of a spalyed first row of hanger wires which are required to maintain position of acoustical suspension systems. Also, temporary clamps are sometimes employed to hold tees to the wall molding. Even then the first row of cross-tees may fall out since there are normally no cross-tee attachment holes in the wall molding. This in turn normally means that the first row of cross-tees have to be measured and cut exactly in the field, rather than being pre-cut or gang cut. This again is a time consuming and labor intensive operation.
Also, rather short lengths of cross-tees are difficult to maintain in proper position and tend to lift off the molding, and when using screw slot grid members, these normally have to be fastened firmly to the wall molding.